I've still got a working Zen Vision M (great mp3 player) and Zen docking station, but sorry to say that the proprietary connector on the Vision M was the only device that would allow docking / charging with the Zen dock.
The ZVM dock does of course have a standard line in, which will allow you to connect an ipod / mp3 / mobile phone, but won't of course charge or work with the supplied remote control.
I now use my Samsung mobile for every day listening /journey to work and just use my still great ZVM (old though it may be) and dock, in the flat. Hopefully, it's still got many years left in it.